Surgical device for spinal fixation

ABSTRACT

Surgical instruments, methods, and systems are provided for securing spinal fixation elements to bone. For example, a spinal fixation system is provided that has a receiver with proximal and distal ends. The proximal end of the receiver is configured to receive various fixation members, such as spinal rods and set screws, therein. The distal end of the receiver has a hook member that is operably coupled thereto and has an opening that is configured to receive bone therein. The hook member is configured to be secured to bone without penetrating the bone.

FIELD

Surgical devices, systems, and methods for spinal fixation are providedherein.

BACKGROUND

Various fixation devices are commonly used in surgery to align and/orfix a desired relationship between various bone structures within apatient. For example, spinal fixation devices are used in orthopedicsurgery to achieve a desired relationship between adjacent vertebralbodies. Such fixation devices typically include one or more spinalfixation elements, such as fixation rods, that can be coupled toadjacent vertebrae by attachment to various bone anchoring devices, suchas hooks, bolts, wires, screws, and the like that are embedded invertebral bodies. In some instances, closure elements, such as screws ornuts, can be used to couple fixation devices to various bone anchoringdevices.

However, the anchor assemblies are often secured to bone throughpenetration of the bone, such as by screws, bolts, and the like. Bonepenetration can be detrimental to the patient. For example, it can causeinfection, screw breakage, screw misplacement, subsidence, bone fracturepropagation, and other complications.

Thus, there remains a need for surgical instruments, methods, andsystems for securing spinal fixation elements to bone.

Accordingly, a spinal fixation system is provided herein that isconfigured to be secured to bony anatomy, for example a spinal fixationsystem that can be secured without the need to penetrate bone.

SUMMARY

Surgical instruments, methods, and systems are provided for securingspinal fixation elements to bone. In a first aspect, a spinal fixationsystem is provided that includes a receiver configured to receive atleast one fixation member. The receiver has a first end defined byopposed arms with a channel therebetween that is configured to receivethe at least one fixation member and a second end that is operablycoupled to a hook member. The hook member has an open portion that isconfigured to engage a portion of bone. A cable is attachable to thereceiver, and it is configured to encircle the bone to extend across theopen portion to secure the receiver to the bone without penetrating thebone. A closure member is insertable between the opposed arms of thereceiver, and it is configured to compress the fixation member into thereceiver.

The spinal fixation system can have a number of variations. For example,the hook member can have a distal-most blade portion that forms an edgeof the open portion, the blade portion can have a channel therethroughto receive a first end of the cable. In another example, the cable ispre-curved such that the cable is configured to be passed around lamina.The receiver can also have at least first and second receiving membersthereon that are configured to receive corresponding first and secondends of the cable, and the first and second ends of the cable can beconfigured to be crimped to secure them in the first and secondreceiving members. In another example, each of the opposed arms can havea loop thereon that is configured to receive an end of the cabletherethrough. In some examples, the at least one fixation member caninclude a spinal rod, and the closure member can include a set screw.

In another aspect, a spinal fixation system is provided that has areceiver configured to receive at least one fixation member. Thereceiver can have a first end defined by opposed arms with a channeltherebetween that is configured to receive the at least one fixationmember and a second end. A hook member is operably coupled to the secondend of the receiver, and the hook member has an open portion that isconfigured to engage a portion of bone to secure the receiver to thebone without penetrating the bone. The hook member can be configured tomove relative to the receiver from an open position allowing release ofthe bone to a closed position securely gripping the bone when the boneis received in the open portion. The system also has a closure memberinsertable between the opposed arms of the receiver, and it isconfigured to compress the fixation member into the receiver.

The spinal fixation system can have a number of variations. For example,the hook member can operably couple to the receiver through a threadedshaft, and the hook member can be configured to move relative to thereceiver from the open position to the closed position through rotationof the threaded shaft. The spinal fixation system can also include a cammechanism that is configured to move the hook member relative to thereceiver from the open position to the closed position. In anotherexample, the cam mechanism can have an arm configured to cause actuationof the cam mechanism when the arm is pivoted from a proximal position toa distal position. In one example, the spinal fixation system can alsoinclude a cam lock that is configured to prevent release of the cammechanism after the cam mechanism has moved the hook member to theclosed position. In some examples, the cam lock can be configured toprevent release of the cam mechanism when the cam lock contacts thefixation member received in the receiver. The spinal fixation system canalso include a ratchet mechanism configured to move the hook memberrelative to the receiver from the open position to the closed position.In one example, the ratchet mechanism can include an arm and a spring,and the arm can be configured to pivot from a disengaged position inwhich the hook member is in the open position to an engaged position inwhich the hook is in the closed position. The spring is configured toresist movement of the arm. In another example, the hook member can havea bone-engaging surface that faces the open position of the hook memberthat is rougher than a non-bone engaging surface thereof. Thebone-engaging surface can be configured to grip the bone receivedthereagainst.

In another aspect, a spinal fixation method is provided that includesinserting bone into an open portion of a hook member on a distal end ofa receiver. The method also includes encircling the bone with a cableattached to the receiver to secure the hook member to the bone withoutpenetrating the bone such that the cable extends across the openportion. The method also includes inserting a spinal rod into a channeldefined by opposed arms on a proximal end of the receiver of thesurgical device, and rotating a set screw between the opposed arms tosecure the spinal rod into the channel.

The method can have numerous variations. For example, the method canalso include passing first and second ends of the cable throughreceiving members on the receiver. In another example, the method caninclude, after passing the first and second ends through the receivingmembers, crimping each of the first and second ends to secure the cableto the receiver and the receiver to the bone. The method can alsoinclude passing the first end of the cable through a channel formed in adistal-most blade portion of the hook member, and the channel can be oneof the receiving members. In some examples, the cable can be apre-curved cable, and encircling the bone with the cable can includepassing the cable through a first secure engagement on a distal end ofthe hook member, beneath and around the bone, along a posterior of aspine of a patient, and through a second secure engagement on thereceiver.

BRIEF DESCRIPTION OF DRAWINGS

The embodiments described above will be more fully understood from thefollowing detailed description taken in conjunction with theaccompanying drawings. The drawings are not intended to be drawn toscale. For purposes of clarity, not every component may be labeled inevery drawing. In the drawings:

FIG. 1A is a perspective view of one embodiment of a spinal fixationsystem component;

FIG. 1B is a side view of the spinal fixation system component of FIG.1A secured to a portion of a lamina;

FIG. 1C is a perspective view of the spinal fixation system component ofFIG. 1A;

FIG. 1D is a back view of the spinal fixation system component of FIG.1A with a spinal rod and a set screw;

FIG. 1E is a cross-sectional side view of the spinal fixation systemcomponent of FIG. 1A secured to a portion of a lamina;

FIG. 2A is a perspective view of another embodiment of a spinal fixationsystem component;

FIG. 2B is a perspective view of the spinal fixation system component ofFIG. 2A;

FIG. 2C is a perspective view of the spinal fixation system component ofFIG. 2A;

FIG. 2D is a top-down partial cross-sectional view of another embodimentof a spinal fixation system component similar to the spinal fixationsystem component of FIG. 2A;

FIG. 3A is a perspective view of another embodiment of a spinal fixationsystem component;

FIG. 3B is a perspective view of the spinal fixation system component ofFIG. 3A;

FIG. 3C is a side view of the spinal fixation system component of FIG.3A;

FIG. 3D is a side view of the spinal fixation system component of FIG.3A attached to a spinal rod;

FIG. 4A is a perspective view of another embodiment of a spinal fixationsystem component;

FIG. 4B is a perspective view of the spinal fixation system component ofFIG. 4A;

FIG. 4C is a side view of the spinal fixation system component of FIG.4A;

FIG. 5A is a perspective view of another embodiment of a spinal fixationsystem component;

FIG. 5B is a perspective view of the spinal fixation system component ofFIG. 5A;

FIG. 5C is a side view of the spinal fixation system component of FIG.5A;

FIG. 5D is a cross-sectional side view of the spinal fixation systemcomponent of FIG. 5A;

FIG. 6A is a perspective view of another embodiment of a spinal fixationsystem component;

FIG. 6B is a side view of the spinal fixation system component of FIG.6A;

FIG. 6C is a top down view of the spinal fixation system component ofFIG. 6A;

FIG. 7A is a perspective view of another embodiment of a spinal fixationsystem component;

FIG. 7B is a side view of the spinal fixation system component of FIG.7A; and

FIG. 7C is a top down view of the spinal fixation system component ofFIG. 7A.

DETAILED DESCRIPTION

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those skilled in the art will understand that the devices andmethods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the present invention is defined solely by the claims. Thefeatures illustrated or described in connection with one exemplaryembodiment may be combined with the features of other embodiments. Suchmodifications and variations are intended to be included within thescope of the present invention.

Further, in the present disclosure, like-named components of theembodiments generally have similar features, and thus within aparticular embodiment each feature of each like-named component is notnecessarily fully elaborated upon. Additionally, to the extent thatlinear or circular dimensions are used in the description of thedisclosed systems, devices, and methods, such dimensions are notintended to limit the types of shapes that can be used in conjunctionwith such systems, devices, and methods. A person skilled in the artwill recognize that an equivalent to such linear and circular dimensionscan easily be determined for any geometric shape. Sizes and shapes ofthe systems and devices, and the components thereof, can depend at leaston the anatomy of the subject in which the systems and devices will beused, the size and shape of components with which the systems anddevices will be used, and the methods and procedures in which thesystems and devices will be used.

Various exemplary methods, devices, and systems are provided forsecuring a fixation system to one or more portions of spinal anatomy,such as lamina, in a patient without penetrating the spinal anatomy.Spinal fixation devices that are used in spinal and orthopedic surgerytypically include one or more spinal fixation elements, such as fixationrods, that can be coupled to adjacent vertebrae by as a result of beingattached and secured within various anchor assemblies. The anchorassemblies can include screws, bolts, and the like that can be securedto the spinal fixation elements through the use of various implants,securing means, or fastening members, such as nuts. The anchorassemblies are often secured to spinal anatomy through penetration ofthe spinal anatomy, such as by the screws, bolts, and the like. Beingsecured through penetration can provide strong fixation between theanchor assemblies and the spinal anatomy. However, in some cases, thispenetration can potentially weaken the spinal anatomy or causeinfection, screw breakage, screw misplacement, and other complicationsfor the patient and the surgeon. Accordingly, spinal fixation systemsare provided herein that are configured to be secured to spinal anatomy,and some of the systems are configured to be secured without penetratingthe spinal anatomy.

An exemplary spinal fixation system has a receiver with proximal anddistal ends. The proximal end of the receiver is configured to receivevarious fixation members, such as spinal rods and set screws, therein.The distal end of the receiver has a hook member that is operablycoupled thereto and that is configured to define an opening that isconfigured to receive a portion of a spinal anatomy, such as lamina,various other elements on a vertebra or a patient's vertebrate spinalcolumn, etc., therein. The hook member is configured to be secured tothe spinal anatomy without penetrating the spinal anatomy through avariety of means, as discussed below.

FIGS. 1A-1E illustrate one embodiment of a spinal fixation system 100that has a cable 140 that is configured to assist in securing the spinalfixation system 100 to a portion of a spinal anatomy, such as lamina.The spinal fixation system 100 has a receiver 102 with a receiver head104 and a hook member 120, and the hook member 120 extends distally fromthe receiver head 104 and defines an opening 122 that is configured toreceive the portion of spinal anatomy in an open portion thereof. Thecable 140 is configured to extend across the opening 122 such that, whenthe portion of spinal anatomy is received in the opening 122, the cable140 is configured to be tightened across the opening 122 and secure thehook member 120 to the spinal anatomy without penetrating the spinalanatomy.

In the exemplary embodiment shown in FIGS. 1A-1E, the receiver head 104is configured to receive various spinal fixation members, such as aspinal rod, and is integrally formed with the hook member 120.Accordingly, the receiver head 104 has opposed arms 106 at a proximalend thereof with a channel 108 between the arms 106 that is configuredto receive the spinal fixation members. The opposed arms 106 havethreading on surfaces facing the channel 108 that is configured toengage with various closure members, such as a set screw, after a spinalfixation member is received therein. The receiver head 104 also has atleast one cable engagement mechanism thereon that is configured toreceive at least one end of the cable 140. As illustrated in FIGS.1A-1E, the engagement mechanism is in the form of loops 110 on opposedsides of the receiver head 104. However, the engagement mechanism on thereceiver head 104 can take a variety of other forms, such as variousloops, pins, closures, hooks, etc.

As noted above, the hook member 120 is of a shape that defines anopening that is configured to receive a portion of spinal anatomy, suchas lamina, therein. The hook member 120 includes a hook arm 121 thatextends distally from the receiver head 104 and a blade 124 at a distalend of the hook arm that extends at an angle α relative to the hook armto form one edge of the opening 122. The blade 124 can be orientedrelative to the hook arm 121 at any suitable angle. An angle ofapproximately 90 degrees is shown in FIGS. 1A-1E, however a personskilled in the art will appreciate that the angle α can be anywhere inthe range from about 45 degrees to about 130 degrees. In the embodimentof FIGS. 1A-1E, the hook member 120 is integral with the receiver head104, however one skilled in the art will appreciate that the hook member120 can be formed separately from the receiver head 104. The blade 124also has a bone-engaging surface 128 that faces spinal anatomy to bereceived in the opening 122. Although the bone-engaging surface 128 anda bone-engaging surface 129 that is opposing the bone-engaging surface128 across the opening 122 shown in FIGS. 1A-1E are smooth, thebone-engaging surfaces can include a roughened surface portion toenhance bone-gripping ability to increase static and dynamic frictionbetween the spinal anatomy and the hook member to prevent slipping oncethe hook member is implanted. For example, the bone-engaging surfacescan be grit-blasted.

The hook member 120 has at least one cable engagement mechanism thereonthat is configured to receive at least one end of the cable 140. Asillustrated in FIGS. 1A-1E, the engagement mechanism is in the form of achannel 126 that extends from a front face of the blade 124 to a backface thereof. However, the engagement mechanism is not limited theretoand can take the form of various loops, pins, closures, hooks, etc.

The cable 140 is configured to secure the hook member 120 to spinalanatomy by closing the opening 122 when spinal anatomy is receivedtherein and the cable is tightened. As illustrated, one end of the cable140 can be received in the at least one cable engagement mechanism onthe receiver head 104 and the at least one cable engagement mechanism onthe hook member 120. For example, as illustrated in FIGS. 1A-1E, thecable 104 has first and second ends 142, 144 that are received in one ofthe loops 110 formed on the receiver head 104 and the channel 126 of theblade 124 in the hook member 120. However, the cable 140 can engage withvarious mechanisms on the receiver 102 to close the opening 122. Thefirst and second ends 142, 144 are crimped close after passing throughthe loop 110 and the channel 126 and the cable 140 is tightened. Asillustrated, the first and second ends of the cable can be enlarged withrespect to the body of the cable, or the cable may include terminalcaps. It is to be understood that a variety of securing means can beused, such as adhesives, welding, clips, etc. In various embodiments,the cable can be pre-curved to assist with placement, such as assistingwith insertion below bony anatomy, and/or to curve the cable away fromvarious parts of a patient's body. For example, the cable can be curvedposteriorly away from neural elements, including the spinal cord.

In use, the spinal fixation system 100 is inserted into a body of apatient. A selected portion of the spinal anatomy, such as a portion ofa lamina 160 illustrated in FIG. 1B, is inserted into the opening 122 ofthe hook member 120. The cable 140 is wrapped around the spinal anatomy,and each of the first and second ends 142, 144 are secured to thereceiver 102 after pulling the cable 140 tight across the opening 122and into securing engagement with the spinal anatomy. The first andsecond ends 142, 144 are passed through the loop 110 and the channel 126and crimped on the other side to keep the cable 140 secured in placewith respect to the receiver 102 and the spinal anatomy. While the cable140 is only passed around spinal anatomy once in the illustratedembodiment, the cable 140 can be passed around spinal anatomy andthrough the receiver 102 multiple times if needed, especially todistribute any load placed on the spinal anatomy. A spinal fixationmember, such as a spinal rod 150 as illustrated in FIG. 1D, is insertedinto the channel 108 and a closure member, such as a set screw 152 asillustrated in FIG. 1D, is threaded between the opposed arms 106. Theclosure member is then rotated into a secured engagement with thefixation member secure the fixation member with respect to the receiver102 and the closure member. In an embodiment with a pre-curved cable, aselected portion of the spinal anatomy, such as a portion of lamina, isstill inserted into the hook member. The cable is then introduced bythreading it through the channel of the blade, underneath the lamina,and out of the spinal canal between adjacent level laminae. The cable isthen passed through the upper loop on the receiver head, where the cableis crimped.

While in the embodiment of FIGS. 1A-1E, the receiver head 104 and thehook member 120 are immovable relative to each other, the hook membercan be configured to move relative to the receiver head in otherembodiments. For example, FIGS. 2A-2C illustrate another embodiment of aspinal fixation system 200 similar to the spinal fixation system 100.However, the spinal fixation system 200 has a hook member 220 that isconfigured to be movable relative to a receiver head 204 such thatmovement of the hook member 220 secures the spinal fixation system 200to a portion of spinal anatomy, such as lamina. The spinal fixationsystem 200 has a receiver 202 with the receiver head 204 and the hookmember 220, and the hook member 220 extends distally from the receiverhead 204 and defines an opening 222 that is configured to receive theportion of spinal anatomy in an open portion thereof. The hook member220 is configured to move proximally toward the receiver head 204 sothat, when the spinal anatomy is received in the opening 222, the hookmember 220 securely grips the spinal anatomy within the opening 222between the hook member 220 and the receiver head 204 to secure thereceiver 200 to the spinal anatomy without penetrating the spinalanatomy.

In the exemplary embodiment shown in FIGS. 2A-2C, the receiver head 204is configured to receive various spinal fixation members, such as aspinal rod. Accordingly, it has opposed arms 206 at a proximal endthereof with a channel 208 between the arms 206 that is configured toreceive a spinal fixation member. The opposed arms 206 have threading onsurfaces facing the channel 208 that is configured to engage withvarious closure members, such as a set screw, after a spinal fixationmember is received therein.

The receiver head 204 is also configured to receive a proximal end ofthe hook member 220 when the hook member 220 is moved proximally. Itthus has a hook engagement portion 205, which can be in the form of aflange, associated therewith. The engagement portion 205 can have acavity formed therein that is configured to facilitate engagement with aportion of the hook member 220. The cavity of the hook engagementportion 205 has a channel therethrough that is configured to receive athreaded shaft 240, discussed in detail below. The receiver head 204 isangularly offset at an angle β from the hook member 220 while the hookengagement portion 205 is aligned with the hook member 220. The receiverhead 204 can be oriented relative to the hook member 220 at any suitableangle. An angle of approximately 45 degrees is shown in FIGS. 2A-2C,however a person skilled in the art will appreciate that the angle β canbe anywhere in the range from about 0 degrees to about 90 degrees.

Similar to the hook member 120, the hook member 220 is of a shape thatdefines an opening that is configured to receive a portion of spinalanatomy, such as lamina, therein. The hook member 220 includes a hookarm 221 that extends distally from the receiver head 204 and a blade 224at a distal end of the hook arm that extends at an angle relative to thehook arm to define one edge of the opening 222. While the illustratedangle of the blade 224 is approximately 90 degrees, the blade 224 canextend at a variety of angles similar to the angle α, discussed abovewith respect to FIGS. 1A-1E. The blade 224 has a bone-engaging surface,i.e., defining a portion of opening 222, that securely grips a portionof spinal anatomy, such as lamina, in the opening 222 when the hookmember 220 moves proximally into the receiver head 204. While theillustrated bone-engaging surface is smooth, it can be rougher thansurrounding surfaces to better grip the spinal anatomy, such as having atextured surface that results from a process such as grit-blasting.

As noted above, the hook member 220 is configured to move proximallyinto the receiver head 204 to engage with and close onto spinal anatomyreceived in the opening 222, and it is not integral with the receiverhead 204 so as to allow relative movement between the hook member andthe receiver head. The hook member 220 has a channel 226 defined thereinthat is axially aligned with the channel of the hook engagement portion205 and is also configured to receive the threaded shaft 240 therein. Aninner surface of the channel 226 is at least partially threaded toengage with corresponding threads on the threaded shaft 240, and thehook member 220 is configured to move proximally and distally withrespect to the receiver head 204 upon rotation of the threaded shaft 240in one direction or the other. While the inner surface of the channel226 has threading thereon, one skilled in the art will understand thatvarious threaded components can be added to the channel 226, such asnuts, to provide a corresponding threading to engage the threaded shaft240 while maintaining a smooth inner surface.

As noted, the threaded shaft 240 is configured to cause relativemovement between the hook member 220 and the receiver head 204, and itthus has a drivable head that rests against a surface of the hookengagement portion and an elongate, threaded body that extends throughthe channels of the receiver head 204 and the hook member 220. Upon adriver tool being used to rotate the head of the threaded shaft 240, thethreaded body is configured to rotate and cause the relative movementbetween the receiver head 204 and the hook member 220 in either proximalor distal direction, depending on the direction of rotation. In someembodiments, the threaded shaft can have a swage or nut distal end toprevent the hook member and the receiver head from being disengaged fromone another.

In use, the spinal fixation system 200 is inserted into a body of apatient. A selected portion of the spinal anatomy, such as the lamina,is inserted into the opening 222 of the hook member 220. A driver toolis used to rotate the threaded shaft 240, which causes the hook member220 to retract towards the receiver head 204. Threading in the channel226 of the hook member 220 engages with threading on the threaded shaft226 to cause the hook member to translate up and down depending on thedirection of rotation. As the threaded shaft 226 is rotated, the hookmember 220 moves from an open position to a closed position in whichspinal anatomy in the opening 222 is secured between the receiver head204 and the hook member 220. A spinal fixation member, such as a spinalrod, is inserted into the channel 208 and a closure member, such as aset screw, is threaded between the opposed arms 206. When any requiredspinal adjustments are made, the closure member is then rotated into asecured engagement with the fixation member such that the fixationmember cannot move with respect to the receiver 202 or the closuremember.

FIG. 2D illustrates another embodiment of a spinal fixation system 250that is similar to the spinal fixation system 200. For example, thespinal fixation system 250 has a hook member 270 that is configured tobe movable relative to a receiver head 254 such that movement of thehook member 270 secures the spinal fixation system 250 to a portion ofspinal anatomy, such as lamina. The spinal fixation system 250 has areceiver 252 with the receiver head 254 and the hook member 270, and thereceiver head 254 is configured to receive various spinal fixationmembers, such as a spinal rod 282. It has opposed arms 256 at a proximalend thereof that are configured to receive a set screw 280 therebetween.The receiver head 254 has a hook engagement portion 255 with a cavityformed therein that is configured to facilitate engagement with aportion of the hook member 270. The cavity of the hook engagementportion 255 has a channel therethrough that is configured to receive athreaded shaft 260, and the hook member 270 has a channel 276 definedtherein that is axially aligned with the channel of the hook engagementportion 255 and is also configured to receive the threaded shaft 260therein. An inner surface of the channel 276 is at least partiallythreaded to engage with corresponding threads on the threaded shaft 260,and the hook member 270 is configured to move proximally and distallywith respect to the receiver head 254 upon rotation of the threadedshaft 260 in one direction or the other. However, unlike the spinalfixation system 200, the threaded shaft 260 has a swage distal end 261,and a bone-engaging surface 275 is rougher than surrounding surfaces tobetter grip the spinal anatomy.

Hook members can move relative to receiver heads in a variety of waysother than as described above. For example, FIGS. 3A-3D illustrateanother embodiment of a spinal fixation system 300 similar to the spinalfixation system 200. However, the spinal fixation system 300 has a hookmember 320 that is configured to be movable relative to a receiver head304 by a cam mechanism. The spinal fixation system 300 has a receiver302 with the receiver head 304 and the hook member 320, and the hookmember 320 extends distally from the receiver head 304 and defines anopening 322 that is configured to receive spinal anatomy in an openportion thereof. A cam mechanism 340 engages both the receiver head 304and the hook member 320, and actuation of the cam mechanism 340 isconfigured to cause proximal movement of the hook member 320 relative tothe receiver head 304 to securely grip the spinal anatomy within theopening 322 without penetrating the spinal anatomy.

In the exemplary embodiment shown in FIGS. 3A-3D, the receiver head 304is configured to receive various spinal fixation members, such as aspinal rod 370. Accordingly, the receiver head has opposed arms 306 on aproximal end thereof with a channel 308 between the arms 306 that isconfigured to receive a spinal fixation member. The opposed arms 306have threading on surfaces facing the channel 308 that is configured toengage with various closure members, such as a set screw, after a spinalfixation member is received therein.

The receiver head 304 is also configured to receive a proximal end ofthe hook member 320 when the hook member 320 is moved proximally. Assuch, it engages the cam mechanism 340 on a distal portion 310 thereof.A longitudinal opening 360 is defined in a distal portion 310 of thereceiver head 304 that is configured to allow a cam bar 350 of the hookmember 320, discussed below, to slide therealong during actuation of thecam mechanism 340 and relative movement of the hook member 320.

The hook member 320 is of a similar shape to the hook members describedabove with respect to FIGS. 1A-1E and 2A-2C in that it defines anopening that is configured to receive a portion of spinal anatomy, suchas lamina, therein. The hook member 320 includes a hook arm 321 thatextends distally from the receiver head 304 and a blade 324 at a distalend of the hook arm that extends at an angle relative to the hook arm todefine one edge of the opening 222. While the illustrated angle of theblade 324 is approximately 90 degrees, the blade 324 can extend at avariety of angles similar to the angle α, discussed above with respectto FIGS. 1A-1E. The blade 324 has a bone-engaging surface that isconfigured to securely grip spinal anatomy in the opening 322 uponactuation of the cam mechanism 340. While the illustrated bone-engagingsurface is smooth, it can be rougher than surrounding surfaces to bettergrip the spinal anatomy, such as having a textured surface that resultsfrom a process such as grit-blasting.

As noted, the hook member 320 is configured to move proximally into thereceiver head 304 upon actuation of the cam mechanism 340, and it is notintegral with the receiver head 304 so as to allow relative movementbetween the hook member and the receiver head. The hook arm 321terminates in the cam bar 350, which slides along the longitudinalopening 360 of the receiver head 304. The cam bar 350 is configured toengage the cam mechanism 340 and move proximally upon actuation thereof,causing the hook member 320 to move proximally with movement of the cambar 350.

The cam mechanism 340 is thus configured to cause relative movementbetween the hook member 320 and the receiver head 304 upon itsactuation. As such, the cam mechanism 340 has wings 342 disposed onopposite sides of the distal portion 310 of the receiver head 304, andeach wing 342 has a plurality of teeth or grooves formed thereon. Thegrooves are configured to receive the cam bar 350 of the hook member 320thereon, and they are angled to allow the cam bar 350 to only moveproximally along the wings 342 during actuation of the cam mechanism340. The cam mechanism 340 has an actuation bar 344 that extends behindthe receiver head 304 and connects the two wings 342. Each wing 342 ispivotably coupled to opposite distal surfaces of the receiver head 304such that movement of the actuation bar 344 causes correspondingrotation of the wings 342 about pivot points 340 p.

In use, the spinal fixation system 300 is used similar to the system200. However, when a selected portion of the spinal anatomy, such as thelamina, is first inserted into the opening 322 of the hook member 320,the cam mechanism is initially in a non-actuated position with the hookmember 320 at a distal-most, open position relative to the receiver head304, as illustrated in FIG. 3D. The cam bar 350 is initially positioneddistally in the longitudinal opening 360 of the receiver head 304 andrests in corresponding groves on each of the wings 342, as noted in FIG.3D at Position 1. Once the receiver 302 is in position on the spinalanatomy, force is applied to the actuation bar 344 distally through useof a tool, such as a cervical compressor instrument, and the actuationbar 344 rotates distally away from the receiver head 304, as illustratedby an arrow in FIG. 3D, causing the wings 342 to rotate in the samedirection about the pivot points. As the wings 342 rotate, the angledgrooves apply an upward, proximally directed force on the cam bar 350 ofthe hook member 320 to lift it proximally along the longitudinal opening360 toward the receiver head 304 such that the cam bar 350 will entereach subsequent groove on the wings 342, as illustrated at Positions 2,3, and 4 of FIG. 3D. As the actuation bar 344 completes its rotation,the cam mechanism 340 comes to a rest with the cam bar 350 in a proximalposition along the longitudinal opening 360, with the result that thehook member 320 has been moved proximally to a closed position with thecam bar 350 to grip spinal anatomy between the hook member 320 and thereceiver head 304. The distance that the cam bar 350 (and thus the hookmember 320) is moved by the cam mechanism 340 depends on a size of thespinal anatomy within the opening 322 such that the cam bar 350 mightnot enter every groove on each wing 342, and the angled grooves assistin maintaining the hook member 320 in the proximal position.

Once the cam mechanism has been activated, it can be configured to lockthe hook member in the closed position engaged with spinal anatomyduring use. As illustrated in FIGS. 4A-4C, another embodiment of aspinal fixation system 400 is provided that is similar to the spinalfixation system 300 with a cam mechanism 340. The spinal fixation system400 has a receiver 402 with a receiver head 404 and a hook member 420,and the hook member 420 extends distally from the receiver head 404 anddefines an opening 422 that is configured to receive a portion of spinalanatomy, such as lamina, in an open portion thereof. A cam mechanism 440engages both the receiver head 404 and the hook member 420, andactuation of the cam mechanism 440 is configured to cause proximalmovement of the hook member 420 relative to the receiver head 404 tosecurely grip the spinal anatomy within the opening 422 withoutpenetrating the spinal anatomy.

As with the receiver head 304 described above, the receiver head 404 isconfigured to receive various spinal fixation members, such as a spinalrod. Accordingly, the receiver head has opposed arms 406 on a proximalend thereof with a channel 408 between the arms 406 that is configuredto receive a spinal fixation member. The opposed arms 406 have threadingon surfaces facing the channel 408 that is configured to engage withvarious closure members. The receiver head 404 is also configured toreceive a proximal end of the hook member 420 when the hook member 420is moved proximally, and thus it has a longitudinal opening 460 thereinthat is configured to allow a cam bar 450 of the hook member 420 toslide therealong during actuation.

Similar to the hook member 320, the hook member 420 is configured tomove proximally into the receiver head 404 upon actuation of the cammechanism 440, and it has a blade 424 that can extend at various anglessimilar to the angle α and a hook arm 421 that terminates in the cam bar450, which is configured to engage the cam mechanism 440 and moveproximally upon actuation thereof. This movement is configured to causethe blade 424 of the hook member 420 to move proximally, as well. Whilea bone-engaging surface of the blade 424 is smooth, it can be rougherthan surrounding surfaces to better grip the spinal anatomy, such ashaving a textured surface that results from a process such asgrit-blasting.

The cam mechanism 440 is similar to the cam mechanism 340 discussedabove, as it is configured to cause relative movement between the hookmember 420 and the receiver head 404 upon actuation. Wings 442 aredisposed on opposite sides of the receiver head 404 and configured torotate about pivot points 440 p, and each wing 442 has angled teeth orgrooves formed thereon. An actuation bar 444 extends behind the receiverhead 404 and connects the two wings 442.

However, the cam mechanism 440 is configured to lock itself in place,and thus lock the hook member 420 in the closed position. In theillustrated embodiment, the cam mechanism is able to lock itself inplace when a spinal fixation member, such as a spinal rod, is receivedin the receiver head 404. The cam mechanism 440 has a panel 452 that isconfigured to engage and apply a distally directed force to the cam bar450. As such it has a saddle 454 integrally formed with the panel 452that receives a force from the spinal fixation member. The saddle 454 isconfigured to sit in the channel 408, and the panel 452 extends along aback of the receiver head 404 and rests on top of the cam bar 450.Because of this arrangement, the saddle 454 is configured to be held inplace by a spinal fixation member placed on top of the saddle 454 in thechannel 408, and the panel 452, in turn, is configured to be held inplace by the saddle 454, which subsequently holds the cam bar 450 inplace.

During placement, the cam mechanism 440 can be actuated similar to thecam mechanism 340 by applying a distally directed force to the actuationbar 444 by a variety of tools. Thus, the saddle 454 and the panel 452 donot apply sufficient force on the cam bar 450 to prevent movement.However, once the receiver 402 has been placed and the hook member 420has engaged the spinal anatomy, a spinal fixation member is attached tothe receiver 402 and subsequently prevents any proximal movement by thesaddle 454 and the panel 452, which keeps the cam bar 450 locked toprevent it from being released until the spinal fixation member has beenremoved.

FIGS. 5A-5D illustrate another embodiment of a spinal fixation system500 similar to the spinal fixation system 300. However, the spinalfixation system 500 has a hook member 520 that is configured to bemovable relative to a receiver head 504 by a ratchet mechanism. Thespinal fixation system 500 has a receiver 502 with the receiver head 504and the hook member 520, and the hook member 520 extends distally fromthe receiver head 504 and defines an opening 522 that is configured toreceive a portion of spinal anatomy, such as lamina, in an open portionthereof. A ratchet mechanism 540 engages both the receiver head 504 andthe hook member 520, and actuation of the ratchet mechanism 540 isconfigured to cause proximal movement of the hook member 520 relative tothe receiver head 504 to securely grip the spinal anatomy within theopening 522 without penetrating the spinal anatomy.

Similar to the receiver head 304, the receiver head 504 is configured toreceive various spinal fixation members, such as a spinal rod, therein.Accordingly, it also has opposed arms 506 on a proximal end thereof witha channel 508 between the arms 506 that is configured to receive aspinal fixation member, similar to the other embodiments discussedabove. The opposed arms 506 have threading on surfaces facing thechannel 508 that is configured to engage with various closure members.

The receiver head 504 is also configured to receive a proximal end ofthe hook member 520 when the hook member 520 is moved proximally. Thereceiver head 504 has a longitudinal opening 560 in a distal portion 510thereof, which is configured to allow ratchet pins 526 of the hookmember 520 to slide therealong, as discussed below. Angled teeth 510 textend from a surface of the distal portion 510 that is configured toengage corresponding angled teeth 521 t of a hook arm 521 of the hookmember 520, as discussed below.

The hook member 520 is of a similar shape as discussed above thatdefines an opening that is configured to receive spinal anatomy therein.The hook member 520 includes the hook arm 521 that extends distally fromthe receiver head 504 and a blade 524 at a distal end of the hook armthat extends at an angle relative to the hook arm to define one edge ofthe opening 522. While the illustrated angle of the blade 524 isapproximately 90 degrees, it can extend at a variety of angles similarto the angle α discussed above with respect to FIGS. 1A-1E. The blade524 has a bone-engaging surface that is configured to securely gripspinal anatomy in the opening 522 upon actuation of the ratchetmechanism 540. While the bone-engaging surface is smooth as illustrated,it can be rougher than surrounding surfaces to better grip the spinalanatomy, such as having a textured surface that results from a processsuch as grit-blasting.

As noted, the hook member 520 is configured to move proximally into thereceiver head 504 upon actuation of the ratchet mechanism 540 due tointeraction between the angled teeth 510 t, 521 t, as discussed below,and it has ratchet pins 526 that extend therefrom and are configured toslide along the longitudinal opening 560 to guide its movement. Theratchet pins 526 are configured to engage the ratchet mechanism 540 andmove proximally upon actuation thereof, causing the hook member 520 andthe blade 524 to move proximally with movement of the ratchet pins 526.

The ratchet mechanism 540 is consequently configured to cause movementof the hook member 520 toward the receiver head 504 upon actuation. Ithas a lever 541 protruding from the distal portion 510 of the receiverhead 504 that engages with the ratchet pins 526 of the hook member 520and is configured to rotate about a pivot point 540 p. As illustrated inFIG. 5D, the angled teeth 510 t, 521 t of each of the receiver head 504and the hook member 520 are held in engagement by a spring 530 extendingfrom the receiver head 540, and the lever 541 is configured to rotatedistally about the pivot point 540 p to force the ratchet pins 526proximally upon distal actuation of the lever by a tool. The forceapplied to the lever 540 is configured to cause angled interactionbetween the angled teeth 510 t, 521 t that forces the hook arm 521 tomove away from the distal portion 510 of the receiver head 504 and pressagainst the spring 530 until the spring bias is overcome and the angledteeth 510 t, 521 t slide past each other as the hook arm 521 movesproximally until the angled teeth 510 t, 521 t fall into a newengagement, resulting in distal movement of the hook member 520 and theratchet mechanism 540 locking in place.

Thus, in use, the ratchet mechanism 540 operates similarly to the cammechanism 340 by causing the hook member 520 to move proximally towardthe receiver head 504 upon distal actuation of the lever 541.

In addition to closing an opening in a hook member or moving a hookmember relative to a receiver head, another mechanism for securing ahook member to spinal anatomy without spinal anatomy penetration caninclude using a screw or pin to engage a portion of spinal anatomy, suchas lamina, in the opening of the hook member. For example, FIGS. 6A-6Cillustrate another embodiment of a spinal fixation system 600 that issimilar to the spinal fixation systems above, but it includes a screw640 that is configured to secure the spinal fixation system 600 to aportion of spinal anatomy, such as lamina. The spinal fixation system600 has a receiver 602 with a receiver head 604 and a hook member 620,and the hook member 620 extends distally from the receiver head 604 anddefines an opening 622 that is configured to receive spinal anatomy inan open portion thereof. The screw 640 is configured to extend into theopening 622 such that, when the spinal anatomy is received in theopening 622, the screw 640 is configured to be tightened against thespinal anatomy to secure the spinal anatomy in the opening 622, and thusto secure the hook member 620 to the spinal anatomy, without penetratingthe spinal anatomy.

The receiver head 604 is configured to receive various spinal fixationmembers, such as a spinal rod. As such, the receiver head 604 hasopposed arms 606 on a distal end thereof with a channel 608 between thearms 606 that is configured to receive a spinal fixation member. Theopposed arms 606 have threading on surfaces facing the channel 608 thatis configured to engage with various closure members, such as a setscrew, after a spinal fixation member is received therein, and thevarious closure members are separate from the screw 640.

Furthermore, the receiver head 604 is configured to allow the screw 640to extend therefrom into the opening 622 to secure spinal anatomy in theopening 622. A threaded opening 610 is defined in a base of the receiverhead 604 that is in communication with the channel 608 and the opening622, and it is configured to receive the screw 640 therethrough. Theopening 610 is positioned below any contacting surface of any spinalfixation member so as not to interfere with placement of spinal fixationmembers in the channel 608.

As noted, the hook member 620 is of a shape that defines an opening thatis configured to receive spinal anatomy therein. The hook member 620includes a hook arm 621 that extends distally from the receiver head 604and a blade 624 at a distal end of the hook arm that extends at an anglerelative to the hook arm to define one edge of the opening 622. Whilethe illustrated angle of the blade 624 is approximately 90 degrees, itcan extend at a variety of angles similar to the angle α discussed abovewith respect to FIGS. 1A-1E. The blade 624 has a bone-engaging surface628 thereon that faces spinal anatomy received in the opening 622. Inthe illustrated embodiment, the hook member 620 is integral with thereceiver head 604, however one skilled in the art will appreciate thatthe hook member 620 can be formed separately. While the bone-engagingsurface 628 is smooth in FIGS. 6A-6C, the bone engaging surface can berougher than surrounding surfaces to better grip the spinal anatomy,such as having a textured surface that results from a process such asgrit-blasting.

As noted, the screw 640 is configured to extend into the opening 622 andsecure spinal anatomy therein, however the screw 640 is configured notto penetrate spinal anatomy. Rather, the screw 640 is configured toapply a distally directed force to spinal anatomy to secure the spinalanatomy between a distal tip of the screw 640 and the bone-engagingsurface 628 of the blade 624. The screw 640 is a flat-bottomed screwthat, when secured against spinal anatomy, has a driver head on a distalend thereof that is configured to sit below any contacting surface ofany spinal fixation members in the channel 608. The driver head of thescrew is configured to receive a tool therein to rotate the screw intoor out of the opening 622.

While the screw 640 is discussed above is useful in one embodiment,various other protuberances can be used to secure spinal anatomy in theopening, for example pins, bumps, columns, and the like. When using oneor more of these alternative embodiments, a saddle can also be placed inthe bottom of the channel to receive a spinal fixation member thereonand force the pin, bump, etc. proximally into secured engagement withthe spinal anatomy. Various springs, friction-fit locking mechanisms,and the like can also be used to provide distal pressure on the pin,bump, etc. to maintain engagement with spinal anatomy.

In use, the spinal fixation system 600 is used similar to the systemsdiscussed above. However, when a selected portion of the spinal anatomy,such as the lamina is inserted into the opening 622 of the hook member620, the screw 640 is driven into the opening 622 and pressed againstthe spinal anatomy to secure the spinal anatomy between the flat distaltip of the screw 640 and the blade 624 of the hook member 620. Once thescrew 640 is tightened against the spinal anatomy, the receiver 602 issecured on the spinal anatomy. A spinal fixation member, such as aspinal rod, is then inserted into the channel 608 and a closure member,such as a set screw, is threaded between the opposed arms 606.

While the screw 640 and the various protuberances discussed above areconfigured not to penetrate bone, a spinal fixation system 700 similarto the system 600 can be used with a pin 740 or screw that is configuredto penetrate bone. As illustrated in FIGS. 7A-7C, the spinal fixationsystem 700 has a receiver 702 with a receiver head 704 and a hook member720, and the hook member 720 extends distally from the receiver head 704and defines an opening 722 that is configured to receive spinal anatomyin an open portion thereof. The pin 740 is configured to extend into theopening 722 such that, when the spinal anatomy is received in theopening 722, the pin 740 can be driven through an opening or channel inthe receiver head 704 into the opening 722 and pressed against thespinal anatomy to secure the spinal anatomy between a distal tip of thepin 740 and a blade of the hook member. However, during placement, thepin 740 at least partially penetrates the spinal anatomy, thus securingthe hook member 700 and the receiver 700 generally to the spinal anatomyin a secure fit. As illustrated, the pin 740 has an upper saddle 742that is configured to sit in the receiver head 704. A spring 744 sitsbetween the upper saddle 742 and the receiver head 704 to keep thesaddle 742 biased proximally out of engagement with any spinal anatomyin the opening 722. When a spinal fixation member, such as a spinal rod,is inserted into the receiver head 704 and tightened into place,however, the spinal fixation member sits on the saddle 742 and forcesthe pin 740 distally into the opening 722 as it overcomes the springbias. The sharp distal point of the pin 740 is thus forced distally intospinal anatomy in the opening to cause the pin 740 to at least partiallypenetrate the spinal anatomy therein and secure the receiver 702 to thespinal anatomy. Other embodiments can use other protuberances that areconfigured to penetrate bone in much the same way as the pin 740, suchas screws. For example, in some embodiments, a receiver similar to thereceiver 602 discussed above can incorporate a screw with a distal pointthat penetrates into spinal anatomy during placement.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. Thedevice can be reconditioned for reuse after at least one use.Reconditioning can include any combination of the steps of disassemblyof the device, followed by cleaning or replacement of particular pieces,and subsequent reassembly. In particular, the device can bedisassembled, and any number of the particular pieces or parts of thedevice can be selectively replaced or removed in any combination. Uponcleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present application.

The devices and components described herein may be processed before use.First, a new or used instrument is obtained and if necessary cleaned.The instrument can then be sterilized. In one sterilization technique,the instrument is placed in a closed and sealed container, such as aplastic or TYVEK bag. The container and instrument are then placed in afield of radiation that can penetrate the container, such as gammaradiation, x-rays, or high-energy electrons. The radiation killsbacteria on the instrument and in the container. The sterilizedinstrument can then be stored in the sterile container. The sealedcontainer keeps the instrument sterile until it is opened in the medicalfacility.

It is preferred that device is sterilized. This can be done by anynumber of ways known to those skilled in the art including beta or gammaradiation, ethylene oxide, steam, and a liquid bath (e.g., cold soak).An exemplary embodiment of sterilizing a device including internalcircuitry is described in more detail in U.S. Pat. Pub. No. 2009/0202387filed Feb. 8, 2008 and entitled “System And Method Of Sterilizing AnImplantable Medical Device.” It is preferred that device, if implanted,is hermetically sealed. This can be done by any number of ways known tothose skilled in the art.

One skilled in the art will appreciate further features and advantagesof the described devices and methods based on the above-describedembodiments. Accordingly, the present disclosure is not to be limited bywhat has been particularly shown and described, except as indicated bythe appended claims. All publications and references cited herein areexpressly incorporated herein by reference in their entirety.

What is claimed is:
 1. A spinal fixation system, comprising: a receiverconfigured to receive at least one fixation member, the receiver havinga first end defined by opposed arms with a channel therebetween that isconfigured to receive the at least one fixation member and a second end,the second end being operably coupled to a hook member having an openportion that is configured to engage a portion of bone, the hook memberhaving a distal-most blade portion that forms an edge of the openportion; a cable attachable to the receiver and to the blade portion ofthe hook member, the cable being configured to encircle the bone toextend across the open portion to secure the receiver to the bonewithout penetrating the bone; and a closure member insertable betweenthe opposed arms of the receiver and configured to compress the fixationmember into the receiver.
 2. The spinal fixation system of claim 1,wherein the blade portion having a channel therethrough to receive afirst end of the cable.
 3. The spinal fixation system of claim 1,wherein the cable is pre-curved such that the cable is configured to bepassed around lamina.
 4. The spinal fixation system of claim 1, whereinthe receiver has at least first and second receiving members thereonconfigured to receive corresponding first and second ends of the cable,one of the at least first and second receiving members being on theblade portion, and the first and second ends of the cable are configuredto be crimped to secure them in the first and second receiving members.5. The spinal fixation system of claim 1, wherein each of the opposedarms has a loop thereon configured to receive an end of the cabletherethrough.
 6. The spinal fixation system of claim 1, wherein the atleast one fixation member comprises a spinal rod, and the closure membercomprises a set screw.
 7. A spinal fixation system, comprising: areceiver configured to receive at least one fixation member, thereceiver having a first end defined by opposed arms with a channeltherebetween that is configured to receive the at least one fixationmember and a second end, a hook member operably coupled to the secondend of the receiver, the hook member having an open portion that isconfigured to engage a portion of bone to secure the receiver to thebone without penetrating the bone, the hook member being configured tomove relative to the receiver from an open position allowing release ofthe bone to a closed position securely gripping the bone when the boneis received in the open portion; a cam mechanism configured to move thehook member relative to the receiver from the open position to theclosed position, the cam mechanism having an arm extending between firstand second cam wings, the arm being configured to cause actuation of thecam mechanism when the arm is pivoted from a proximal position to adistal position; and a closure member insertable between the opposedarms of the receiver and configured to compress the fixation member intothe receiver.
 8. The spinal fixation system of claim 7, furthercomprising a cam lock configured to prevent release of the cam mechanismafter the cam mechanism has moved the hook member to the closedposition.
 9. The spinal fixation system of claim 8, wherein the cam lockis configured to prevent release of the cam mechanism when the cam lockcontacts the fixation member received in the receiver.
 10. The spinalfixation system of claim 7, wherein the hook member has a bone-engagingsurface facing the open position of the hook member that is rougher thana non-bone engaging surface thereof, the bone-engaging surface beingconfigured to grip the bone received thereagainst.
 11. The spinalfixation system of claim 8, wherein the cam lock is positioned at leastpartially within the receiver.
 12. The spinal fixation system of claim7, wherein the first and second cam wings are positioned on oppositesides of the receiver and the hook member from each other.
 13. Thespinal fixation system of claim 7, wherein the first cam wing isconfigured to pivot about a first pivot point, the second cam wing isconfigured to pivot about a second pivot point, and the arm isconfigured to pivot about the first and second pivot points.
 14. Aspinal fixation method, comprising: inserting a bone into an openportion of a hook member on a distal end of a receiver; encircling thebone with a cable attached to the receiver and a distal-most bladeportion of the hook member to secure the hook member to the bone withoutpenetrating the bone, the cable extending across the open portion;inserting a spinal rod into a channel defined by opposed arms on aproximal end of the receiver of the surgical device; and rotating a setscrew between the opposed arms to secure the spinal rod into thechannel.
 15. The spinal fixation method of claim 14, further comprisingpassing a first end of the cable through a first receiving member on theblade portion of the hook member and a second end of the cable through asecond receiving member on the receiver.
 16. The spinal fixation methodof claim 15, further comprising, after passing the first and second endsthrough the first and second receiving members, crimping each of thefirst and second ends to secure the cable to the receiver and thereceiver to the bone.
 17. The spinal fixation method of claim 15,further comprising passing the first end of the cable through a channelformed in the blade portion of the hook member, the channel being thefirst receiving member.
 18. The spinal fixation method of claim 14,wherein the cable is a pre-curved cable, and encircling the bone withthe cable includes passing the cable through a first secure engagementon the blade portion of the hook member, beneath and around the bone,along a posterior of a spine of a patient, and through a second secureengagement on the receiver.